The key stat from Flurry’s research is a look at apps that are available in the iTunes App Store, Google Play (formerly known as the Android Market) and Amazon’s Appstore. Not surprisingly, the same app in all three stores makes more money — specifically through in-app purchases — in iTunes, so Flurry used this data as a baseline, setting iOS revenues to be 100%. It turns out that in this situation, Amazon Appstore revenues are 89 percent of iOS revenues, while Google Play yields only 23 percent.

Flurry puts it in dollar terms like this:

Another way to interpret the results is that for every $1.00 an app generates in the iTunes App Store, it generates $0.89 in the Amazon Appstore and $0.23 in Google Play.

These results illustrate two very important trends. First, it may make sense for developers writing Android apps to get them in Amazon’s store sooner rather than later. Second, it shows that making money on Android apps is possible; the same title can make almost as much money as its iOS counterpart. Granted, working with Amazon may not be ideal to some, given that Amazon can set the app price. But giving up that freedom may prove financially beneficial in the long run thanks to Amazon’s constant promotion of mobile apps.

I think that’s part of the success factor here for Amazon apps. For all intents and purposes, these titles are the same Android apps found in Google Play. Google isn’t known as a brand for digital media and apps, however. Instead, it’s commonly considered to be a search company first and everything else second.

Compare that to Amazon, which is a top retail brand around the world: Last year, Amazon’s brand value surpassed that of WalMart to take the top retail brand spot. This mindset, that Amazon is a safe place to purchase digital content — think e-books, music, and video — extends to apps and in-app purchases, even if they’re the same wares found in Google’s store. Clearly, consumers are comfortable with Apple’s brand and store too, so devs may want to focus on iOS and Amazon when it comes to mobile apps.